Cerebral and somatic near-infrared spectroscopy monitors are commonly used to detect
tissue oxygenation in various circumstances. This form of monitoring is based on tissue
infrared absorption and can be influenced by several physiological and non-physiological
factors that can induce error in the interpretation. This narrative review explores
those clinical and technical limitations and proposes solutions and alternatives in
order to avoid some of those pitfalls.
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Published online: July 21, 2020
Footnotes
Abbreviations: ∆A, change in optical density; a, extinction coefficient of chromophore; A, light attenuation coefficient; B, path length factor; c, concentration of chromophore; cox, co-oximetry; CPB, cardiopulmonary bypass; DHCA, Deep Hypothermic Circulatory Arrest; HbO2, oxyhemoglobin; HHb, deoxygenated hemoglobin; L, length between light entry and exit; LDF, Laser-Doppler flowmeter; NIRS, near-infrared spectroscopy; nm, nanometer; rSO2, regional oxygen saturation; rScO2, regional cerebral oxygen saturation; SD, standard deviation; SjO2, jugular bulb oxygen saturation; SRS, spatially resolved spectroscopy; THb, total hemoglobin; tNIRS-1, tissue oximeter using time resolved spectroscopy; TOI, tissue oxygen index
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